Surface Permanent Magnet Synchronous Motors’ Passive Sensorless Control: A Review

Sensorless control of permanent magnet synchronous motors is nowadays used in many industrial, home and traction applications, as it allows the presence of a position sensor to be avoided with benefits for the cost and reliability of the drive. An estimation of the rotor position is required to perform the field-oriented control (FOC), which is the most common control scheme used for this type of motor. Many algorithms have been developed for this purpose, which use different techniques to derive the rotor angle from the stator voltages and currents. Among them, the so-called passive methods have gained increasing interest as they do not introduce additional losses and current distortion associated instead with algorithms based on the injection of high-frequency signals. The aim of this paper is to present a review of the main passive sensorless methods proposed in the technical literature over the last few years, analyzing their main features and principles of operation. An experimental comparison among the most promising passive sensorless algorithms is then reported, focusing on their performance in the low-speed operating region

Double input DC-DC converter for highly flexible and reliable Battery Storage Systems

Battery storage systems are fundamental in UPS applications. UPSs are exploited when high reliability is required. A DC-DC converter is typically used to interface the battery to the inverter to match the different voltage levels. In normal operation, the battery of the UPS is not used and it intervenes only during grid blackout. However, the battery is subjected to deterioration and UPS intervention could fail. In medium and high power UPS, more battery modules are connected in series. If one battery is damaged, all the series is affected. To prevent this issue, a new double-input DC-DC converter is presented in this paper. The two DC sources can be controlled separately, resulting in a system reliability improvement. In addition, the damaged battery is not bypassed; hence the overall system performance can be maximized, since the deteriorated battery can provide energy at a limited rate. Additionally, the proposed converter allows batteries based on different technologies to be mixed together, achieving the best performances from each technology

State-Space Approach for SPMSM Sensorless Passive Algorithm Tuning

Sensorless algorithms for Permanent Magnet Synchronous Motors (PMSM) have achieved increasing interest in the technical literature over the last few years. They can be divided into active methods and passive methods: the first inject high-frequency signals exploiting rotor anisotropy, whereas the second are based on observers. Recently, a sensorless control based on a rotor flux observer has been presented in the technical literature, which gives very accurate results in terms of rotor position estimation and robustness. In this paper, the aforementioned observer is considered and a procedure for choosing stabilizing gains of the observer is proposed. The contribution of the paper is three-fold: the mathematical modelling of the rotor flux observer, the methodology for the definition of the observer gains, and the presentation of the experimental results

Stability Analysis of Open-Loop V/Hz Controlled Asynchronous Machines and Two Novel Mitigation Strategies for Oscillations Suppression

Asynchronous machines are always widely used in most industrial applications due to their reliability, flexibility, and manoeuvrability. To achieve variable speed operations, the quite simple open-loop V/Hz control is largely utilized. Under open-loop V/Hz control, the nonlinear interaction is well known to cause current and torque oscillations while operating at low to medium speeds under light loads. This article presents the stability analysis of induction motors at low–medium frequencies under no-load conditions with the V/Hz control. A system representation in the form of state space is discussed, and the region of instability is plotted against the V/f plane. Two novel and refined methods for the mitigation of oscillations in the region of instability are presented. The two proposed algorithms are finally tested and validated through simulation on an inverter-fed induction motor drive system

Stability Analysis of Open-Loop V/Hz Controlled Asynchronous Machines and Two Novel Mitigation Strategies for Oscillations Suppression

Asynchronous machines are always widely used in most industrial applications due to their reliability, flexibility, and manoeuvrability. To achieve variable speed operations, the quite simple open-loop V/Hz control is largely utilized. Under open-loop V/Hz control, the nonlinear interaction is well known to cause current and torque oscillations while operating at low to medium speeds under light loads. This article presents the stability analysis of induction motors at low–medium frequencies under no-load conditions with the V/Hz control. A system representation in the form of state space is discussed, and the region of instability is plotted against the V/f plane. Two novel and refined methods for the mitigation of oscillations in the region of instability are presented. The two proposed algorithms are finally tested and validated through simulation on an inverter-fed induction motor drive system

Induction Motor Field-Oriented Sensorless Control with Filter and Long Cable

In recent years, part of the efforts of the electric drive researcher has been focused on the study of sensorless control algorithms that allow controlling the machine without a speed measure and with ever-fewer measurement devices. This article proposes a possible solution for the submarine application of an asynchronous motor. The motor is designed to drive a petrol pump at a depth of three thousand meters. The motor is fed by an inverter that is located on an offshore platform, and they are connected through a filter and a cable that is 19.74 km long. In this application, it is not suitable to use a speed measurement device; in fact, at this depth it is important to use as few components as possible, in order to increase the system reliability. A control algorithm that only needs available electrical measures is proposed below

Timing of onset affects arthritis presentation pattern in antisyntethase syndrome

79To evaluate if the timing of appearance with respect to disease onset may influence the arthritis presentation pattern in antisynthetase syndrome (ASSD).nonenoneGonzález-Gay, Miguel A; Montecucco, Carlomaurizio; Selva-O'Callaghan, Albert; Trallero-Araguas, Ernesto; Molberg, Ovynd; Andersson, Helena; Rojas-Serrano, Jorge; Perez-Roman, Diana Isabel; Bauhammer, Jutta; Fiehn, Christoph; Neri, Rossella; Barsotti, Simone; Lorenz, Hannes M; Doria, Andrea; Ghirardello, Anna; Iannone, Florenzo; Giannini, Margherita; Franceschini, Franco; Cavazzana, Ilaria; Triantafyllias, Konstantinos; Benucci, Maurizio; Infantino, Maria; Manfredi, Mariangela; Conti, Fabrizio; Schwarting, Andreas; Sebastiani, Giandomenico; Iuliano, Annamaria; Emmi, Giacomo; Silvestri, Elena; Govoni, Marcello; Scirè, Carlo Alberto; Furini, Federica; Lopez-Longo, Francisco Javier; Martínez-Barrio, Julia; Sebastiani, Marco; Manfredi, Andreina; Bachiller-Corral, Javier; Sifuentes Giraldo, Walter Alberto; Cimmino, Marco A; Cosso, Claudio; Belotti Masserini, Alessandro; Cagnotto, Giovanni; Codullo, Veronica; Romano, Mariaeva; Paolazzi, Giuseppe; Pellerito, Raffaele; Saketkoo, Lesley Ann; Ortego-Centeno, Norberto; Quartuccio, Luca; Batticciotto, Alberto; Bartoloni Bocci, Elena; Gerli, Roberto; Specker, Christof; Bravi, Elena; Selmi, Carlo; Parisi, Simone; Salaffi, Fausto; Meloni, Federica; Marchioni, Enrico; Pesci, Alberto; Dei, Giulia; Confalonieri, Marco; Tomietto, Paola; Nuno, Laura; Bonella, Francesco; Pipitone, Nicolò; Mera-Valera, Antonio; Perez-Gomez, Nair; Gerzeli, Simone; Lopez-Mejias, Raquel; Matos-Costa, Carlo Jorge; Pereira da Silva, Jose Antonio; Cifrian, José; Alpini, Claudia; Olivieri, Ignazio; Blázquez Cañamero, María Ángeles; Rodriguez Cambrón, Ana Belén; Castañeda, Santos; Cavagna, LorenzoGonzález-Gay, Miguel A; Montecucco, Carlomaurizio; Selva-O'Callaghan, Albert; Trallero-Araguas, Ernesto; Molberg, Ovynd; Andersson, Helena; Rojas-Serrano, Jorge; Perez-Roman, Diana Isabel; Bauhammer, Jutta; Fiehn, Christoph; Neri, Rossella; Barsotti, Simone; Lorenz, Hannes M; Doria, Andrea; Ghirardello, Anna; Iannone, Florenzo; Giannini, Margherita; Franceschini, Franco; Cavazzana, Ilaria; Triantafyllias, Konstantinos; Benucci, Maurizio; Infantino, Maria; Manfredi, Mariangela; Conti, Fabrizio; Schwarting, Andreas; Sebastiani, Giandomenico; Iuliano, Annamaria; Emmi, Giacomo; Silvestri, Elena; Govoni, Marcello; Scirè, Carlo Alberto; Furini, Federica; Lopez-Longo, Francisco Javier; Martínez-Barrio, Julia; Sebastiani, Marco; Manfredi, Andreina; Bachiller-Corral, Javier; Sifuentes Giraldo, Walter Alberto; Cimmino, Marco A; Cosso, Claudio; Belotti Masserini, Alessandro; Cagnotto, Giovanni; Codullo, Veronica; Romano, Mariaeva; Paolazzi, Giuseppe; Pellerito, Raffaele; Saketkoo, Lesley Ann; Ortego-Centeno, Norberto; Quartuccio, Luca; Batticciotto, Alberto; Bartoloni Bocci, Elena; Gerli, Roberto; Specker, Christof; Bravi, Elena; Selmi, Carlo; Parisi, Simone; Salaffi, Fausto; Meloni, Federica; Marchioni, Enrico; Pesci, Alberto; Dei, Giulia; Confalonieri, Marco; Tomietto, Paola; Nuno, Laura; Bonella, Francesco; Pipitone, Nicolò; Mera-Valera, Antonio; Perez-Gomez, Nair; Gerzeli, Simone; Lopez-Mejias, Raquel; Matos-Costa, Carlo Jorge; Pereira da Silva, Jose Antonio; Cifrian, José; Alpini, Claudia; Olivieri, Ignazio; Blázquez Cañamero, María Ángeles; Rodriguez Cambrón, Ana Belén; Castañeda, Santos; Cavagna, Lorenz

Timing of onset affects arthritis presentation pattern in antisynthetase syndrome

Objective To evaluate if the timing of appearance with respect to disease onset may influence the arthritis presentation pattern in antisynthetase syndrome (ASSD). Methods The patients were selected from a retrospective large international cohort of ASSD patients regularly followed-up in centres referring to AENEAS collaborative group. Patients were eligible if they had an antisynthetase antibody testing positive in at least two determinations along with arthritis occurring either at ASSD onset (Group 1) or during the course of the disease (Group 2). Results 445 (70%; 334 females, 110 males, 1 transsexual) out of the 636 ASSD we collected had arthritis, in the majority of cases (367, 83%) from disease onset (Group 1). Patients belonging to Group 1 with respect to Group 2 had an arthritis more commonly polyarticular and symmetrical (p=0.015), IgM-Rheumatoid factor positive (p=0.035), erosions at hands and feet plain x-rays (p=0.036) and more commonly satisfying the 1987 revised classification criteria for rheumatoid arthritis (RA) (p=0.004). Features such as Raynaud's phenomenon, mechanic's hands and fever (e.g. accompanying findings) were more frequently reported in Group 2 (p=0.005). Conclusion In ASSD, the timing of appearance with respect to disease onset influences arthritis characteristics. In particular, RA features are more common when arthritis occurs from ASSD onset, suggesting an overlap between RA and ASSD in these patients. When arthritis appears during the follow-up, it is very close to a connective tissue disease-related arthritis. Also, the different prevalence of accompanying features between these two groups is in line with this possibility

Timing of onset affects arthritis presentation pattern in antisyntethase syndrome

OBJECTIVES: To evaluate if the timing of appearance with respect to disease onset may influence the arthritis presentation pattern in antisynthetase syndrome (ASSD). METHODS: The patients were selected from a retrospective large international cohort of ASSD patients regularly followed-up in centres referring to AENEAS collaborative group. Patients were eligible if they had an antisynthetase antibody testing positive in at least two determinations along with arthritis occurring either at ASSD onset (Group 1) or during the course of the disease (Group 2). RESULTS: 445 (70%; 334 females, 110 males, 1 transsexual) out of the 636 ASSD we collected had arthritis, in the majority of cases (367, 83%) from disease onset (Group 1). Patients belonging to Group 1 with respect to Group 2 had an arthritis more commonly polyarticular and symmetrical (p=0.015), IgM-Rheumatoid factor positive (p=0.035), erosions at hands and feet plain x-rays (p=0.036) and more commonly satisfying the 1987 revised classification criteria for rheumatoid arthritis (RA) (p=0.004). Features such as Raynaud's phenomenon, mechanic's hands and fever (e.g. accompanying findings) were more frequently reported in Group 2 (p=0.005). CONCLUSIONS: In ASSD, the timing of appearance with respect to disease onset influences arthritis characteristics. In particular, RA features are more common when arthritis occurs from ASSD onset, suggesting an overlap between RA and ASSD in these patients. When arthritis appears during the follow-up, it is very close to a connective tissue disease-related arthritis. Also, the different prevalence of accompanying features between these two groups is in line with this possibility